Purification of ether



Patented June 21, 1938 Walter G. Ghristiansen, Glen Ridge, and William A, Lott, East.0range, N. J., .assignors to E. R.

tion of New York Squibb & Sons, New. York, N. Y., a corpora- No Drawing. Application April 2, 1937,

Serial No. 134,682

r Y 14 Claims. (o1. 260151) This application is a continuation in part'of application Serial No. 635,600, filed September This-invention relates to the purification of ether. 1

Aldehydes form in ether during its manufacture (as by the oxidation of ethyl alcohol in the presence of sulfuric acid) and subsequently (as by the decomposition of peroxides), and consti- Jo tute an impurity that tends to make the ether unfit for anesthetic use.-

It is the object of this invention to provide an efiicient method of removing aldehydes from ether.

In the practice of this invention, aldehydecontaining ether is contacted with a solution of an aryl hydroxide-especially a compound selected from the class consisting of resorcinol, pyrogallol, tannic acid, ortho-phenyl phenol, phenyl oatechol, di-normal-propyl resorcinol, and para-amino phenol-in a solvent comprising a nonvolatile water-miscible alcohol, such as glycerine, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, and the par- 5 tial alkyl ethers thereof. Preferably, the aryl hydroxide solution has been made alkaline; thus, when resorcinol is used, it is particularly advantageous to add at least enough sodium hydroxide to convert it into the disodium com- 30 pound.

The ether treated may be'in the liquid or the vapor state; the contact should be thorough, and may be effected by mixing the liquid ether with the contact solution or passing the ether vapor 36 through suitable scrubbing towers; the solvent for the aryl hydroxide may be anhydrous or water-containing, an anhydrous solvent having the advantage that it does not introduce water into the ether and therefore does not interfere 40 with the maintenance of the desirable low Water content thereof; preliminary neutralization of the liquid ether or ether vapor to remove acidic materials and preliminary dephlegmation of the ether vapor to remove the large proportion of 45 alcohol vapor, are advisable for prolonging the active life of the contact solution; and in the treatment of the ether'vapor the temperature in I the aryl hydroxide scrubber should be kept sufficiently high to prevent the ether from condens- 50 ing, but not much higher.

By. employing the method of this invention, it is possible to reduce aldehydes in ether from a proportion many times in excess of that ordinarily found in anesthetic ether, to less than one part 55 of aldehyde in a million parts of ether.

As'an example, a continuous stream of ether vapor is passed through a scrubber comprising a more or less conventional apparatus consisting of a tall cylindrical chamber jacketed so as to maintain an external temperature of about 40 C. and filled with (a) contact material such as broken clay plates or pebbles-graded so that the largest are at the bottom and the smallest at the top and separated into sections by horizontal screens-and (b) a. solution having the compo- 10 s'ition 4 Resorcinol grams 32 40% sodium hydroxide solution do 114 Ethylene glycol, enough to make. cc 650 (the proportions of sodium hydroxide and resorcinol being such asto form disodium resorcinol). On leaving the scrubber, the ether vapor is freed from any entrained solution and is then condensed. This treatment renders the ether. alde- 20 hyde-free. Among the many alternative contact solutions are such compositions as 2400 cc. of a saturated solution of potassium hydroxide in anhydrous propylene glycol, combined with either (1) 135 grams of tannic acid or (2) 250 grams of ortho-phenyl phenol.

As a further example, liquid ether may be freed from aldehydes by mixing it thoroughly with a solution such as those specified in the foregoing example, especially the resorcinol solution, the

ether being then preferably distilled to eliminate any impurities of low volatility that the contact solution may have introduced.

As a still further example, 100 cc. of liquid anesthetic ether in a 500 cc. separatory funnel is shaken vigorously at about six-minute intervals for half an hour with a solution comprising: 10.04 grams of 36% sodium hydroxide solution; 5 grams of pyrogallol, phenyl catechol, di-normal-propyl resorcinol, or para-amino phenol; and enough 40 monobutyl ether of diethylene glycol to make 100 grams. Thenthe mixture is allowed to stand until complete separation has occurred, and the contact solution is drawn off.

As a yet further examplegany aldehydes in anesthetic ether may be substantially removed and its water content may be minimized, by passing the ether vapor through a scrubber containing a solution of theformula:

} Pounds Resorcinol 6 Sodium hydroxide 8.75 Anhydrous alcohol 24 Ethylene glycol 293 It is to be understood that the foregoing examples are merely illustrative and by no means limitative of the invention, which may be variously otherwise embodiedfor instance, as to the specific aryl hydroxides, solvents, and other ingredients used in the contact solutions, and the procedures and apparatus employed-Within the scope of the appended claims.

We claim:

1. The method of removing aldehydes from ether that comprises contacting the ether with a solution of an aryl hydroxide in a solvent comprising in major proportion a nonvolatile watermiscible alcohol.

2. The method of removing aldehydes from ether that comprises contacting the ether with a solution of an aryl hydroxide in an anhydrous solvent comprising in major proportion a nonvolatile Water-miscible alcohol.

3. The method of removing aldehydes from ether that comprises contacting the ether with a solution of an aryl hydroxide in a water-containing solvent comprising. in major proportion a nonvolatile Water-miscible alcohol.

4. The method of removing aldehydes from ether that comprises contacting the ether with a solution of an aryl hydroxide in an alkalized solvent comprising in major proportion a nonvolatile water-miscible alcohol.

5. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in a solvent comprising in major proportion a nonvolatile water-miscible alcohol.

, 6. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in an anhydrous solvent comprising in major proportion a nonvolatile Water-miscible alcohol.

7. The method of removing aldehydes, from ether that comprises contacting the ether with a solution of resorcinol in a water-containing solvent comprising in major proportion a nonvolatile water-miscible alcohol.

8. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in analkalized solvent comprising in major proportion a nonvolatile watermiscible alcohol.

9. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in a solvent comprising in major proportion ethylene glycol.

10. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in an anhydrous solvent comprising in major proportion ethylene glycol.

11. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in a water-containing solventcomprising in major proportion ethylene glycol. V l r 12. The method of removing aldehydes from ether that. comprises contacting the ether with a solution of resorcinol in an alkalized solvent comprising in major proportion ethylene glycol;

13. The method of removing aldehydes from ether that comprises contacting the ether with a solution of an aryl hydroxide in an anhydrous solvent comprising ethyl alcohol and a nonvolatile water-miscible alcohol, the latter being in major proportion.

14. The method of removing aldehydes from ether that comprises contacting the ether with a solution of resorcinol in an anhydrous alkalized solvent comprising ethyl alcohol and ethylene glycol, the latter being in major proportion.

WALTER G. C'HRISTIANSEN. WILLIAM A. LOTT. 

